After the marsh marigolds have withdrawn their brightness from low-lying meadows, blossoms of yellow avens twinkle in their stead. In autumn the jointed, barbed styles, protruding from the seed clusters, steal a ride by the same successful method of travel to new colonizing ground adopted by burdocks, goose-grass, tick-trefoils, agrimony, and a score of other “tramps of the vegetable world.”